Recently, the issue of security has been a great concern even in households and the like, for example, and various monitoring systems have been devised.
For example, a system has been proposed which involves installing cameras at home, changing the directions of the cameras while away from home using a cell phone, transferring images taken by the cameras to the cell phone, and displaying the images on a display screen of the cell phone (see, for example, Patent Document 1).
Also, a system has been proposed which involves installing abnormality detection sensors and cameras, placing a call to the user's cell phone if any abnormality is detected by any of the abnormality detection sensors, sending a message about the abnormality to the cell phone, and allowing the user to view images taken by the cameras on the cell phone (see, for example, Patent Document 2).
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-61138
[Patent Document 2]
Japanese Patent Laid-Open No. 2001-245069
When installing a system which monitors an empty home during the user's absence using one of the conventional monitoring systems, if the user wants to monitor a particular room or a small number of monitoring points, only a few cameras need to be installed, but if the user wants to monitor a large number of places scattered in the house including the open/close states of windows and the front door, on/off states of air conditioners and lighting apparatus, etc., a large number of cameras need to be installed, which may result in a complicated and extremely expensive system.
To solve this problem, it is conceivable to install a freely movable autonomous mobile robot equipped with a camera, program the robot with a map of the house, and instruct the robot via a cell phone to photograph one or more particular places in the house and send resulting images when the user wants to know conditions in the house while the user is out. The robot moves to the specified place according to the instructions, takes photographs, and sends resulting images to the user's cell phone. This allows the user to display the received images on the display screen of the cell phone and check the conditions of the specified place in the house. In this case, although the robot itself incurs cost, no additional camera other than the one mounted on the robot is required. Also, if there are a large number of places to be monitored in various directions, this configuration may cost less than installing cameras in a large number of places. Besides, the robot will be desirable if it makes the user feel as if it were a pet, doll, or the like.
However, if a robot such as the one described above is used, when the user operates the cell phone to check out conditions in the house, the robot must move to a specified place, take a photograph, and send the image unlike when a camera is installed in each of many places, and thus it is likely that there is a considerable time delay before the user obtains an image of the specified place especially if the robot is originally located away from the specified place. This may make the user feel irritated.
In view of the above circumstances, the present invention has an object to provide a robot system and autonomous mobile robot that can reduce the interval between the time when a command is given and the time when images can be viewed.